1. A believer refers to a person who believes in a certain religion. Now it also refers to people who believe in a certain theory, school, viewpoint or someone;

2. Disciples refer to students who seek knowledge, or knowledgeable and respected people, and academic teachers who preach and dispel doubts;

3. Apostles refer to 12 disciples, who were originally chosen by Jesus Christ and given missionary mission, originally meaning to be sent;

4. A saint refers to a person recognized as a saint by the church in Christianity.